Forget about designer handbags – designer weeds are the future

How resilient are we? The world is changing dramatically – not just politically but socially and environmentally too.

Resilience to change is becoming increasingly important, especially in environmental terms. We need to build the resilience of our environment, and our ecosystems, so that we can cope with ongoing changes in climate.

The thing is that until we find a solution, communities across the world, both human and natural, are going to continue to suffer the impact of extreme events as they happen, often with unpredictable consequences. We’re losing the ability of our environment to absorb shocks and insulate us from flood events, drought events, soil erosion and oceanic warming.

This isn’t an abstract fear: forest fires in France, cleaving of the Larsen C ice shelf, bleaching of the Great Barrier reef corals, declines in seabird populations in Scotland: they are all linked directly to climate change.

An obvious solution is to ensure we have diverse ecosystems. A diverse system is a robust system. Simplified systems and monocultures are all too susceptible to outbreaks of disease and severe climatic fluctuations. Yet species and habitat loss continues across the world to the extent that global biodiversity is no longer within safe limits and continued loss will threaten the planet’s ability to support humans and wildlife (Science, July 2016). Even in the UK, The National Ecosystem Assessments across the UK and the State of Nature reports, reflect the loss of species diversity and habitat simplification. Just as we should be protecting our species and habitat diversity, the opposite is happening.

A timely piece of work then for the new Diversify project, where the crop diversity work at the James Hutton Institute, provided a welcome space last Friday to discuss these issues and how agriculture might help.

Research shows that diverse crop mixtures increase resilience to disease and increase productivity at the same time. In addition there may be a benefit in reducing inputs, such as pesticides and fertiliser, the research on this is less clear to date. But that seems to be reflecting a lack of data rather than anything else.

What’s more, recent greenhouse trials have shown that increasing crop diversity reduces number of weeds and niche space available to weeds. So if increasing diversity in crop mixtures increases crop productivity and reduces the number of common weeds, could we develop crop and native plant mixtures to suppress common weeds, increase crop productivity and conserve native plants all at the same time?

If diversity can promote diversity – could diversity increase resilience by protecting key ecological relationships? And if it could, what role and value is there for native biodiversity?

What, for example, is the role of rare arable plants? Arable plants make up one of the fastest disappearing plant communities across the UK. Weeds that were once common in fields, corn flowers and corn marigolds for example, are now something that catch the eye because we see them so rarely. Could these plants, by taking up some of the habitat niche, limit the space for more common, and arguably less welcome, weeds? It seems unlikely, although the research would be useful. What they can do, however, is provide a nectar and pollen source for beneficial insects – both pollinators and predators, that increase crop productivity. We could, therefore, design, or encourage, native plant communities that provide the benefits to invertebrates and ecological resilience while, at the same time, increasing crop productivity? It seems counter intuitive but the evidence is not pointing away from that.

Research is showing that weed diversity benefits crop biomass. It is heartening is that this is being actively explored and the solution of increasing diversity to build resilience is becoming clearer. With the link to increased productivity as well as more resilient ecosystems, we are building a natural capital argument for agricultural subsidies that support nature not only to ensure nature remains in it full glory for future generations but also because farmers get healthier and more productive crops, while building a more resilient environment.

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Building a future for wild plants

About me

Having trained as a palaeoecologist, I use knowledge of past environments to find innovative and practical ways forward to halt the ongoing loss of biodiversity.
I am Programme Director at GROW Observatory, a citizen science programme, supported by EU Horizon 2020. Working with 18 partners from 10 countries across Europe, the project has started in November 2016 and is working with citizen growers across Europe to gather soil and growing data to build growing advice and test climate models generated by satellite.